Crutches have traditionally included a rubber or resilient tip having an upwardly extending axial recess to receive the lower end of the crutch bow. In use, the tip engages a supporting surface, and being resilient, acts to prevent slippage of the crutch on the surface.
In the past, the lower surface of the crutch tip has been generally concave. In theory, when a load is applied to the crutch, the concave lower surface will deflect to bring the entire lower surface into contact with the supporting surface to obtain a maximum area of surface contact. However, in practice, very rarely is the lower end of the tip positioned flat against the supporting surface when the load is applied, for the tip is usually at an angle to the vertical, with the result that only a small portion of the periphery of the tip actually engages the supporting surface.
In an attempt to more positively direct the load to the entire lower surface of the tip, a metal concave socket has been positioned at the bottom of the recess in the tip and is engaged by the lower end of the crutch bow, as disclosed in U.S. Pat. No. 3,741,226. When a load is applied at a slight angle to the vertical, the socket aids in transmitting the load downwardly into the supporting surface.